Hi,
I’m also trying to model a sequence diagram that links to a “sub-sequence-diagram” using a reference fragment – to achieve something like the model in the EA help…

(Image source:
http://www.sparxsystems.com/enterprise_architect_user_guide/12.0/standard_uml_models/diagramgate.html)
• I’ve created a separate sequence diagram that will serve as the sub-diagram.
• I drop the sub-diagram (…as Interaction Occurrence) into the main diagram and it shows the diagram as a fragment.
• However, I want to create a message from a lifeline of the main diagram to the reference fragment and it does not create.
• I have tried to create a diagram gate in the diagram as well. However, I cannot create a message from a lifeline to the diagram gate either.
I can’t find any documentation that shows the procedure of how to model this, so can you please advise me on how to achieve this? Thanks.